从文件

Question

我有一个样本文件，如下所示：

5    6    7    8
55   66   77   88

A    B    C    D
1    2    3    4
2    4    6    8
3    8    12   16

E    F    G    H
11   22   33   44
and so on...

我想在bash脚本中输入命令，或者只在bash终端中输入命令，以独立于其他列提取其中一列。例如，我想使用pattern = C执行类似grep / awk命令的操作并获得以下输出：

C
3
6
12

如何提取一个独立于其他列的特定列，并在模式后面提取一行以便在我的输出中输入7或G列的上一列？

Answer 1

如果在找到的期限之后总是有3条记录：

awk '{for(i=1;i<=NF;i++) {if($i=="C") col=i}} col>0 && rcount<=3 {print $col; rcount++}' test

这将查看记录中的每个字段，如果找到＆＃34; C＆＃34;，它将捕获列号i。如果列号大于0，则它将打印列的内容。它最多可记录3条记录，然后停止打印。

Answer 2

//Message.java
package Message;
import java.io.*;

public class Message implements Serializable {
    String msg;
    String tag;
    String username;

    private static final long serialVersionUID = 4L;
        // Methods.
    }

    // Reading MessageObjects in Server.java.
    @Override
    public void run() {
        Message message = null;
        try {
            while ((message = (Message)reader.readObject()) != null) {
                // Processing message.
            }
        }
    }

    // Sending Message Objects in android App.
    public void onClick(View v) {
        if(!msgBox.getText().toString().equals("")) {
            final String msg;
            try {
                msg = msgBox.getText().toString();
                writer.writeObject(new Message(msg, CLIENT, username));
                msgBox.setText("");
                writer.flush();
                // Updating ui etc.
            }
            catch (IOException e) {
                 e.printStackTrace();
            }
            textBox.smoothScrollBy(textBox.getMaxScrollAmount(), 100);
        }
    }

    // Connection-method in android app, initalizes streams.
    private boolean connect(String username, String address, int port) {
        boolean connected = false;
        try {
            server = new Socket(address, port);
            InputStreamReader(server.getInputStream());
            reader = new ObjectInputStream(server.getInputStream());
            writer = new ObjectOutputStream(server.getOutputStream());
            writer.writeObject(new Message("!newUser",AUTOMATED,username));
            writer.flush();
            connected = true;
            System.out.println("Connected!");
        }
        catch (Exception ex) {
            ex.printStackTrace();
            System.out.println("Cannot Connect!");
            connected = false;
            // UI-things.
        }
        if(connected){
            // Thread that listens for replies.
            listenThread(); 
        }
        return connected;
    }